The present invention relates to the field of exercise devices and more particularly a ball-shaped exercise device for performing site-specific isometric exercises directed to overall body strengthening and protection against the effects of osteoporosis.
The need for exercise has been increasingly recognized. In addition to the benefits of better overall health and fitness, the strengthening of muscles and bones reduce the risk of fractures of the spine and hips as a major consequence of osteoporosis. Strong muscles stimulate the formation of stronger bones, provide the muscle control that helps to keep one""s balance and prevent falls, help maintain an upright posture and prevent the xe2x80x9cdowager""s humpxe2x80x9d of osteoporosis, and provide shock-absorbing fracture protection to the skeleton when an unavoidable fall occurs.
The present invention addresses isometric exercise, wherein, with little or no movement, one set of muscles is tensed for a period of seconds in opposition to another set of muscles or to an immovable object. Such isometric exercises are thus distinguished from isokinetic exercises wherein a muscle force is applied to a constant velocity of motion, as for example in pulling the handles of a rowing machine, or isotonic exercise when a constant weight is lifted through a range of motion.
Many isometric exercises require or are enhanced by the use of an exercise device providing force(s) that counterbalance the muscular force(s) applied by the exercising person. Amongst a recommended set of isometric exercises, some will require muscles to contract concentrically under uniform fiber tension, while others will require excentric muscular expansion. Accordingly, in the field addressed by present invention, the exercise device must be bidirectional, as distinguished from unidirectional devices, e.g. those utilizing stretch cords or bands, or long thin coil springs that can operate only in tension and cannot operate in compression.
Examples of unidirectional isometric exercise devices are found in U.S. Pat. No. 4,023,808 to Hebert for a RESILIENT FORCE RESISTOR TYPE EXERCISING DEVICE and U.S. Pat. No. 4,852,874 to Sleichtser III et al for a PORTABLE ISOKINETIC EXERCISING DEVICE: these utilize elastic stretch band loops as resistance elements.
Examples of bidirectional isometric exercise devices are found in U.S. Pat. No. 4,376,533 to Kolbel for a PUSH AND PULL TYPE EXERCISING DEVICE and U.S. Pat. No. 4,406,453 to Herzfeld for a PORTABLE EXERCISER: these utilize metal springs as resistance elements.
U.S. Pat. No. 2,115,926 by Hatton for HANDLE FOR INFLATED BALLS AND THE LIKE is of interest in showing an inflated ball with a pair of solid hand grips recessed at diametrically opposite locations of the ball; however the ball is for athletic game purposes only and is not intended or suitable for use as an isometric exercise device as addressed by the present invention.
In the above mentioned examples of known art exercise devices, the handles provided are intended for two-handed operation only, and do not accommodate feet or legs, furthermore they fail to provide a sort accommodating surface that can be applied against various body surfaces.
It is a primary object of the present invention to provide a versatile bidirectional isometric exercise device that can be utilized in conjunction with various body parts such as hands, legs, knees, feet, etc., for exercising muscles in both opposite directions, i.e. not restricted to isotonic exercises.
It is a further object to provide an exercise device directed to overall body and paraspinal strengthening particularly for persons prone to or desiring protection from the effects of osteoporosis.
It is a further object that the exercise device permit soft accommodation to various body surfaces for a broad array of isometric exercises.
It is a further object to realize an exercise device meeting the foregoing objects in a very simple structure that does not require metal springs, stretch cords or the like, or mechanisms such as lever arms.
It is a further object to realize an inflatable exercise device that can be deflated for easy carrying and convenient storage.
The abovementioned objects have been accomplished in the present invention of an inflatable isometric exercise ball, about 46 CM (18xe2x80x3) in diameter, fitted with a pair of strap-like handles, that can also serve as stirrups, located at diametrically opposite regions of surface of the main ball portion. The ball is less than fully inflated so as to interface comfortably with various regions of the body. In a recommended sequence of isometric exercises directed to particular different body regions, some of the exercises utilize the ball in a tension mode with the user""s arms or legs inserted through the handles, while other exercises utilize the ball in a compression mode, squeezed between body parts or between a body part and a wall or floor.
A recommended sequence of exercises may be depicted by graphic illustrations printed directly on the surface of the exercise ball.